1. Field of the Invention
The present invention relates to materials for vacuum devices, vacuum devices used for a vacuum apparatus that generates ultra-high vacuum, a vacuum apparatus, a method of manufacturing materials for vacuum, a method of manufacturing vacuum devices, and a method of manufacturing vacuum apparatus.
2. Description of the Prior Art
The need for a vacuum apparatus which performs an operation in a pressure-reduced atmosphere (may be described as ‘in vacuum’ hereinafter), such as manufacturing apparatus for producing semiconductor devices, an analyzer of materials or the like and a large particle accelerator, are increasingly on the rise. In the vacuum apparatus, vacuum materials have been improved constantly since the degree of vacuum directly relates to the quality of operation.
The following patent document 1 describes a surface treatment of pure copper or various Cu alloys used for the vacuum device, which was created by the same inventor as the inventor of this application. The document describes that the surface treatment is completed in such a manner that surface cleaning by electro-polishing and baking in a vacuum after evacuation for the reduction of an oxide film layer are sequentially performed to make the inner surface of a chamber become a pure metal state. This has enabled the vacuum apparatus such as a sputtering apparatus and a vacuum thermal treatment apparatus to obtain an outgassing rate of approximately 10−11 Pa·m/s (hereinafter, referred to as Pa (H2)·m/s) as a pressure calculated in a hydrogen equivalent (which is taken one order of magnitude lower in a nitrogen equivalent pressure).
[Patent Document 1]
    Japanese Patent Laid-open No.07-002277 publication
Meanwhile, the outgassing rate lower than 10−12 Pa (H2)·m/s has been required in the vacuum apparatus for generating further ultra-high vacuum, and further improvement of the vacuum materials is desired.